The spin observable for spin 1/2 particles is represented by Pauli Matrices acting upon a 2-dimensional Hilbert Space. In RQM, forgetting about the matter-antimatter duality for the moment, that TWO-state Hilbert Space is directly related, through the Lorentz Group, to the TWO separate differential equations in the Dirac Equation. Is that same "TWO-ness" also found in modern QFT for spin 1/2 particles? Are there TWO separate quantum fields for a spin 1/2 particle in modern QFT? As always, thanks in advance.(adsbygoogle = window.adsbygoogle || []).push({});

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# Spin 1/2 in Modern QFT?

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